RESUMO
BACKGROUND: Chronic early trauma alters children's stress reactivity and increases the prevalence of anxiety disorders; yet the neuroendocrine and immune mechanisms underpinning this effect are not fully clear. Animal studies indicate that the mother's physiology and behavior mediate offspring stress in a system-specific manner, but few studies tested this external-regulatory maternal role in human children exposed to chronic stress. METHODS: We followed a unique cohort of children exposed to continuous wartime trauma (N = 177; exposed; N = 101, controls; N = 76). At 10 years, maternal and child's salivary immunoglobulin A (s-IgA) and oxytocin (OT), biomarkers of the immune and affiliation systems, were assayed, maternal and child relational behaviors observed, mother and child underwent psychiatric diagnosis, and child anxiety symptoms assessed. RESULTS: War-exposed mothers had higher s-IgA, lower OT, more anxiety symptoms, and their parenting was characterized by reduced sensitivity. Exposed children showed higher s-IgA, more anxiety disorders and post traumatic stress disorder, and more anxiety symptoms. Path analysis model defined three pathways by which maternal physiology and behavior impacted child anxiety; (a) increasing maternal s-IgA, which led to increased child s-IgA, augmenting child anxiety; (b) reducing maternal OT, which linked with diminished child OT and social repertoire; and (c) increasing maternal anxiety, which directly impacted child anxiety. CONCLUSIONS: Our findings, the first to measure immune and affiliation biomarkers in mothers and children, detail their unique and joint effects on children's anxiety in response to stress; highlight the relations between chronic stress, immune activation, and anxiety in children; and describe how processes of biobehavioral synchrony shape children's long-term adaptation.
Assuntos
Ansiedade/diagnóstico , Imunoglobulina A/metabolismo , Ocitocina/metabolismo , Poder Familiar , Saliva/imunologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Adulto , Ansiedade/epidemiologia , Biomarcadores/metabolismo , Estudos de Casos e Controles , Criança , Comportamento Infantil/psicologia , Pré-Escolar , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Relações Mãe-Filho , Mães/psicologia , Escalas de Graduação Psiquiátrica , Saliva/metabolismo , Transtornos de Estresse Pós-Traumáticos/epidemiologiaRESUMO
Wnt signalling has an important role in cell fate determination, tissue patterning and tumorigenesis. Secreted antagonists of Wnt include Frizzled (Fz)-related proteins (FRPs), Cerberus, Wnt inhibitory factor (WIF) and Dickkopf (Dkk). FRPs, Cerberus and WIF have all been shown to act by binding and sequestering Wnt. We report a novel mechanism of Wnt-signalling inhibition by human Dkk-1. Dkk-1 demonstrated no interaction with Wnt but bound a single cell surface site with high affinity (K(D) = 0.39 nM). Its receptor was detectable in a complex with a relative molecular mass of 240,000 (M(r) 240K) with [(125)I] Dkk-1 by covalent affinity cross-linking. Wnt signalling through beta-catenin is mediated by the Fz receptor and a recently identified low-density-lipoprotein-receptor-related co-receptor, LRP6/Arrow. Overproduction of the 200K LRP6 protein, but not of Fz, strikingly increased Dkk-1 binding as well as the amount of the 240K cross-linked complex, which was shown to be composed of Dkk-1 and LRP6. Moreover, Dkk-1 function was completely independent of Fz but LRP6 dramatically interfered with the Dkk-1 inhibition of Wnt signalling. Thus, unlike Wnt antagonists, which exert their effects by molecular mimicry of Fz or Wnt sequestration through other mechanisms, Dkk-1 specifically inhibits canonical Wnt signalling by binding to the LRP6 component of the receptor complex.
Assuntos
Proteínas/farmacologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores de LDL/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transativadores , Proteínas de Peixe-Zebra , Linhagem Celular , Proteínas do Citoesqueleto/farmacologia , Interações Medicamentosas , Humanos , Immunoblotting , Peptídeos e Proteínas de Sinalização Intercelular , Cinética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Ligação Proteica , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Transfecção , Proteínas Wnt , beta CateninaRESUMO
Sample 10084,40 (fines, less than 1 millimeter) contains substantial amounts of the inert gases. Their concentrations are inversely proportional to particle size; hence the gases appear to be surface-correlated in the soil fragments. The most likely origin of the gas is solar wind or solar cosmic rays. Glass and feldspar are generally poorer in gas than lithic fragments. Ratios of elements in the sample differ significantly from solar values. Ratios of isotopes in the sample are similar to those in meteorites. Argon-40 appears to consist of a radiogenic and a surface-correlated component. An apparent potassium-argon age of 4.42(+0.24)(-0.28) billion years is calculated.
RESUMO
Noninfectious particles of a mutant of Rous sarcoma virus failed to exhibit DNA polymerase activity even with the use of the most sensitive synthetic template-primer complexes. A neutralization blocking test against antibody to DNA polymerase revealed that these mutants did not contain protein immunologically related to the DNA polymerase.
Assuntos
Vírus do Sarcoma Aviário/enzimologia , DNA Nucleotidiltransferases/análise , Nucleotídeos de Adenina/metabolismo , Animais , Antígenos Virais/análise , Vírus da Leucose Aviária/imunologia , Vírus do Sarcoma Aviário/imunologia , Galinhas , DNA Nucleotidiltransferases/metabolismo , Nucleotídeos de Guanina/metabolismo , Mutação , Testes de Neutralização , Polinucleotídeos/metabolismo , Ratos/imunologia , Moldes Genéticos , Nucleotídeos de Timina/metabolismo , TrítioRESUMO
The tumors found in turkeys having lymphoproliferative disease (LPD) are histologically characterized by a pleomorphic population of cells of the lymphoid series. Electron microscopy has shown that, despite marked differences in shape and size, the proliferating cells share basic ultrastructural features, indicating their lymphoid origin. Virus particles morphologically and morphogenetically characteristic of type C oncorna-viruses of Retraviridae were found in different organs and plasma samples of diseased or infected turkeys with LPD. This LPD type C virus resembled members of the reticuloendotheliosis virus group but not members of the avian sarcoma virus group.
Assuntos
Corpos de Inclusão Viral , Transtornos Linfoproliferativos/veterinária , Doenças das Aves Domésticas/patologia , Perus , Animais , Divisão Celular , Transtornos Linfoproliferativos/microbiologia , Transtornos Linfoproliferativos/patologia , Microscopia Eletrônica , Doenças das Aves Domésticas/microbiologia , Retroviridae/ultraestruturaRESUMO
Primary hamster-embryo cells were dispersed in vitro. The frequency of colony development depended on the original method used for dispersing the cells and on the number of cells seeded. Cell populations derived from passages in vitro of 3 colony isolates produced tumors when inoculated into baby or adult hamsters. Similar populations derived from primary or confluent, passaged cell cultures failed to produce tumors. The transformed cells were long, parallel Fibroblasts or short, randomly arranged spindle types. It is suggested that malignant, spontaneous transformation of cells occurs within a limited number of passages in vitro and that these cells may be a factor in virus-induced cell transformations.
Assuntos
Transformação Celular Neoplásica , Animais , Cricetinae , Técnicas In Vitro , Células-Tronco Neoplásicas , Infecções Tumorais por Vírus/patologiaRESUMO
Members of the Wnt family induce mouse mammary tumors and partially transform mammary epithelial cells in culture. However, their mechanism of transformation remains to be elucidated. In NIH3T3 mouse embryo fibroblasts, a standard transformation model, Wnt-1 and Wnt-2 were shown to induce altered properties including increased saturation density and growth in soft agar. Such cells also exhibited increased cell-cell adhesiveness. However, unlike oncogenes such as PDGFB or ras, Wnt-1 and -2 failed to induce detectable transformed foci following transfection, and stable NIH3T3 transfectants lacked tumor forming capacity. Wnt-1 and -2 transfectants exhibited increased uncomplexed, cytosolic beta-catenin, which was not observed with PDGFB, ras or erbB2 transfectants. In transient transfection, Wnt-1 and -2 induced a rapid increase in cytosolic beta-catenin but no detectable increase in the phosphorylated activated forms of MAP kinase. In contrast, ras was a potent activator of MAP kinase but had no effect on free beta-catenin levels. These findings establish that both Wnt signaling and pattern of growth alterations differ from those of oncogenes which activate proliferative signaling pathways in NIH3T3 cells.
Assuntos
Divisão Celular , Transformação Celular Neoplásica , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais , Proteínas de Peixe-Zebra , Células 3T3 , Animais , Adesão Celular , Linhagem Celular Transformada , Humanos , Camundongos , Oncogenes , Proteínas Proto-Oncogênicas/genética , Transfecção , Proteínas Wnt , Proteína Wnt1 , Proteína Wnt2RESUMO
The human homologue of fz1 (Hfz1) was cloned from a cDNA library. Hfz1 was shown to couple to Wnt signal transduction pathways by its ability to enhance Wnt induced TCF dependent transcription in both autocrine and paracrine modes. Enhanced TCF dependent signaling was dose dependent with respect to both Wnt-3A and Hfz1. Moreover, Hfz1 deletion mutants with truncated carboxy termini showed markedly reduced capacity to enhance Wnt signal transduction. Specificity was demonstrated with respect to signal transduction by different Wnts. While Wnt-3a, -3, -1 and to a lesser extent Wnt-2 cooperated with Hfz1 in the paracrine assay for TCF dependent signaling, neither Wnt-4, -5a, -5b, -6, -7a nor -7b did so, despite similar levels of expression. However, coimmunoprecipitation of Hfz1 with both Wnt-3a and Wnt-5a indicated that TCF dependent signaling in response to Wnts is not determined solely by their ability to bind the receptor. All of these findings provide strong evidence that Hfz1 is a functional partner for certain Wnts in inducing TCF dependent transcription.
Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas/metabolismo , Receptores de Neurotransmissores/genética , Receptores de Neurotransmissores/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Peixe-Zebra , Linhagem Celular , Transformação Celular Neoplásica , Clonagem Molecular , Proteínas de Ligação a DNA/genética , Receptores Frizzled , Humanos , Fator 1 de Ligação ao Facilitador Linfoide , Biologia Molecular/métodos , Dados de Sequência Molecular , Mutação , Proteínas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G , Sensibilidade e Especificidade , Análise de Sequência , Transdução de Sinais , Fatores de Transcrição/genética , Transcrição Gênica , Transfecção , Proteínas Wnt , Proteína Wnt-5a , Proteína Wnt2 , Proteína Wnt3 , Proteína Wnt3A , Proteína Wnt4RESUMO
Colorectal cancer (CRC) is one of the most frequent cancers in humans. It develops via a multistage process involving alterations of both protooncogenes and tumor suppressor genes. In the present report we determined the level of expression of several Wnt genes in CRC by RT-PCR and direct sequencing. While Wnt-1 was not detectably expressed in any colonic tissues, Wnt-5a gene was efficiently expressed both in nontumorous as well as in colonic tumor tissues. In contrast, the Wnt-2 gene, which was expressed at low levels in normal colon, exhibited overexpression in all tumor tissue samples at the different Dukes' stages of CRC progression, including premalignant polyps and liver metastases. Overexpression of the Wnt-2 gene occurred also in other digestive neoplasms such as gastric and esophageal carcinomas, as well as in diverticulitis associated with stenosis or pseudo-tumor.
Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Sequência de Bases , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteína Wnt2RESUMO
The turkey c-K-ras(B) transcript and two species of the turkey rap1A transcripts transcribed from two distinct promoters were isolated from a turkey spleen cDNA library. Turkey K-Ras and Rap1A proteins shared extensive amino acid (aa) sequence relatedness throughout their major functional domains: the four GTP-binding domains, the effector region and the C-terminal CAAX box. However, they diverged significantly in their intervening regions. In contrast, almost complete identity in the aa composition was exhibited between turkey K-Ras and Rap1A and their human homologues. The complete conservation that exists between turkey and human Rap1A, also along the polybasic C-terminal domain as opposed to Rap1B, suggests the functional relevance of these divergent residues in specifying the distinct biological functions of these two closely related proteins.
Assuntos
Proteínas de Ligação ao GTP/genética , Genes ras , Regiões Promotoras Genéticas , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar , Humanos , Dados de Sequência Molecular , Proto-Oncogene Mas , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Perus , Proteínas rap de Ligação ao GTPRESUMO
The Tat protein of equine infectious anemia virus, EIAV, was shown to augment viral gene expression, presumably through interaction with the Tat responsive element, TAR. Recently, cell-free polyadenylation assays suggested that perturbation of the EIAV TAR secondary structure diminished polyadenylation efficiency. The present study indicates that the EIAV TAR regulates the efficiency of the 3'-end processing of viral RNA also in transfected cells. Moreover, our data suggest that the provision of the EIAV Tat protein in trans potentiates read-through transcription through the 3' viral long terminal repeat (3' LTR), thus suggesting activation of downstream-located cellular genes.
Assuntos
Regulação da Expressão Gênica , Produtos do Gene tat/metabolismo , RNA Viral/genética , Transcrição Gênica , Animais , Sistema Livre de Células , Primers do DNA , Cães , Genes tat , Cavalos , Mutagênese Sítio-Dirigida , Fases de Leitura Aberta , Reação em Cadeia da Polimerase , Estrutura Secundária de Proteína , Precursores de RNA/genética , Processamento Pós-Transcricional do RNA , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Sequências Repetitivas de Ácido Nucleico , TransfecçãoRESUMO
The lymphoproliferative disease virus of turkeys (LPDV) is the etiological agent of a rapidly developing lymphoproliferative process in turkeys. To better understand the genetic relationships of LPDV to other retroviruses we determined the nucleotide sequence of its pol gene. Comparative computer analyses of the deduced amino acid sequences of the reverse transcriptase and integrase domains within pol established that LPDV represents a distinct class of avian retroviruses that is most closely related to the avian leukemia-sarcoma viruses.
Assuntos
Produtos do Gene pol/genética , Retroviridae/classificação , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Nucleotidiltransferases/genética , DNA Viral , Integrases , Dados de Sequência Molecular , DNA Polimerase Dirigida por RNA/genética , Sequências Repetitivas de Ácido Nucleico , Retroviridae/genética , Homologia de Sequência de Aminoácidos , PerusRESUMO
The Tat protein of equine infectious anemia virus (EIAV) was synthesized in Escherichia coli using the inducible expression plasmid, pET16b, which contains a His.Tag leader, thus allowing for rapid and efficient enrichment of the histidine-tagged protein by metal affinity chromatography. Yields of up to 20 mg of Tat were obtained from 10(11) bacterial cells. The recombinant Tat protein was shown to potently trans-activate the EIAV long terminal repeat (LTR) following its introduction into canine cells by 'scrape loading'. The EIAV Tat protein was found to localize predominantly within the cytoplasm, in contrast to HIV-1 Tat. The availability of large amounts of purified functional EIAV Tat protein should greatly facilitate detailed structure-function analyses.
Assuntos
Produtos do Gene tat/metabolismo , Vírus da Anemia Infecciosa Equina/metabolismo , Sequências Repetitivas de Ácido Nucleico , Ativação Transcricional , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Primers do DNA , Cães , Escherichia coli , Produtos do Gene tat/biossíntese , Produtos do Gene tat/isolamento & purificação , HIV-1/metabolismo , Vírus da Anemia Infecciosa Equina/genética , Dados de Sequência Molecular , Plasmídeos , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Moldes Genéticos , Produtos do Gene tat do Vírus da Imunodeficiência HumanaRESUMO
The lymphoproliferative disease virus (LPDV) is the etiological agent of a lymphoproliferative disease that naturally occurs in turkeys. Recently, we have cloned the LPDV provirus and established it as a replication-competent genome devoid of a viral oncogene [Gak et al., J. Virol. 63 (1989) 2877-2880]. This report presents the nucleotide sequence of its long terminal repeat (LTR) and establishes it as a potent transcriptional element. Several features of the LPDV LTR were similar to those found in the LTRs of the avian sarcoma-leukemia viruses (ASLV) and include the primer-binding site (tRNATrp), the polypurine tract, the organization of the polyadenylation signal, the complexities of the U3, R and U5 regions, as well as a potential secondary structure in U5-R. The LTR sequence diverges significantly from the ASLV LTRs, which share a common structure and have extensive sequence homology mainly in the R and U5 domains. These findings support the conclusion that LPDV represents a distinct class of avian retrovirus, evolutionarily related to the ASLV family.
Assuntos
Transtornos Linfoproliferativos/microbiologia , Doenças das Aves Domésticas/microbiologia , Sequências Repetitivas de Ácido Nucleico/genética , Retroviridae/genética , Transcrição Gênica , Animais , Sequência de Bases , Cloranfenicol/biossíntese , Transtornos Linfoproliferativos/veterinária , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico , PerusRESUMO
The nucleotide sequence of the long terminal repeat (LTR) of caprine arthritis encephalitis virus (CAEV), a prototype lentivirus was determined. 6-bp directly repeated host cell sequences flank the 376-bp proviral LTRs. By comparison with other retroviral sequences, the CAEV LTR likely contains U3, R and U5 regions 207, 86 and 83 base-pairs in length, respectively. Sequences conforming to consensus transcriptional promoter sites were identified in the U3 region upstream of a potential transcription initiation site. A consensus polyadenylation signal is present 20 bases upstream of the putative R-U5 border and a potential poly(A) addition site. Sequence comparisons of the CAEV LTR with those of other retroviruses uncovered significant similarities with that of visna virus. No other global homologies with other retrovirus LTRs could be detected. CAEV utilizes a primer binding site complementary to lysine tRNA as does visna, AIDS associated retroviruses, and mouse mammary tumor virus. The putative primer for positive-strand DNA synthesis identified in the CAEV sequence is identical to that of visna virus and very similar to those of AIDS retroviruses and MMTV. In addition, a stretch that includes the TATA box of the CAEV LTR resembles closely the corresponding region in the AIDS retrovirus. These and other findings further strengthen the classification of AIDS retrovirus as a lentivirus.
Assuntos
DNA Viral/genética , Vírus da Encefalite/genética , Genes Virais , Animais , Sequência de Bases , Cabras , Conformação de Ácido Nucleico , Sequências Repetitivas de Ácido Nucleico , Retroviridae/genética , Especificidade da EspécieRESUMO
The lymphoproliferative disease virus (LPDV) of turkeys is the retroviral agent of etiology of a rapidly developing, naturally occurring, lymphoproliferative process. Recently we have molecularly cloned the viral genome. The lack of a susceptible cell culture which can sustain LPDV replication hampered the analysis of the infectious capability of the cloned genome. Based on the efficient in-vivo replication of LPDV we have developed a sensitive in-vivo approach aimed at establishing the infectious capability of the cloned provirus. According to this approach, peripheral leukocytes withdrawn from 3-week-old turkeys were transfected with the cloned DNA and the transfected leukocytes were re-injected into the turkey from which they had been obtained. The injected leukocytes enabled the efficient expression of the viral genome and the release into the blood stream of LPDV virions, which thereafter could travel to their appropriate in-vivo target lymphoid cells and start multiple replication cycles, resulting in the development of a detectable viremia. The applicability of this in-vivo assay for other cloned viral genomes is discussed.
Assuntos
DNA Viral/isolamento & purificação , Transtornos Linfoproliferativos/microbiologia , Técnicas Microbiológicas , Retroviridae/genética , Animais , Clonagem Molecular , Masculino , DNA Polimerase Dirigida por RNA/sangue , Retroviridae/patogenicidade , Sensibilidade e Especificidade , Transfecção , Perus/microbiologiaRESUMO
Turkeys inoculated at 5 weeks of age with lymphoproliferative disease (LPD) virus developed typical lesions in the spleen, thymus, and pancreas. The in vitro blastogenic response of peripheral blood lymphocytes to the mitogens phytohemagglutinin and concanavalin A was drastically (up to 90%) suppressed in the inoculated turkeys 1 to 4 weeks postinoculation compared with uninoculated controls, and even at 11 weeks the response was about 50% inhibited. A lethal (about LD33) dose of antihelminthic drug niridazole, 100 mg/kg given each day for 3 days to 4-week-old turkeys, caused a transient inhibition of the blastogenic response within 32 days of treatment, which was less pronounced than that observed in turkeys inoculated with LPD virus, whether pretreated with niridazole or not. Virus-associated reverse transcriptase activity in the plasma was significantly higher in the turkeys pretreated with niridazole, and LPD lesions developed to the same extent in the untreated and treated groups, as determined 9 weeks post virus inoculation. A sublethal dose of niridazole, 50 mg/kg given each day for 4 days, did not suppress the blastogenic response to mitogens at any time determined (starting 10 days post-treatment) and did not affect the pathogenesis of LPD and the viremia. Body weights were significantly decreased by virus infection and by treatment with lethal doses of niridazole.
Assuntos
Ativação Linfocitária , Niridazol/farmacologia , Doenças das Aves Domésticas/imunologia , Infecções por Retroviridae/veterinária , Retroviridae/imunologia , Perus , Animais , Feminino , Técnicas In Vitro , Ativação Linfocitária/efeitos dos fármacos , Masculino , Doenças das Aves Domésticas/enzimologia , DNA Polimerase Dirigida por RNA/sangue , Retroviridae/enzimologia , Infecções por Retroviridae/enzimologia , Infecções por Retroviridae/imunologiaRESUMO
Molecular hybridisation with radioactively labelled DNA complementary to the RNA of the maedi virus was used to probe for homologous RNA in the polysome fraction of pulmonary carcinomas (jaagiekte) of Awassi sheep. No sequence homology was detected, which suggests that maedi (or visna) virus is not implicated in the aetiology of pulmonary carcinoma of sheep.
Assuntos
Adenomatose Pulmonar Ovina/metabolismo , RNA Viral/metabolismo , Vírus Visna-Maedi/metabolismo , Animais , DNA Viral/metabolismo , Hibridização de Ácido Nucleico , RNA Neoplásico/metabolismo , OvinosRESUMO
A recently isolated Israeli retrovirus from a sheep with maedi-visna was compared with other retroviruses, using cDNA-RNA hybridization in solution. The Israeli isolate was shown to have close, if not identical, genetic homologic features with the ovine progressive pneumonia virus reported in the United States, rather than with those of the maedivisna viruses of European origin.
Assuntos
Pneumonia Intersticial Progressiva dos Ovinos/diagnóstico , Animais , Europa (Continente) , Ovinos , Estados Unidos , Vírus Visna-Maedi/isolamento & purificaçãoRESUMO
Lymphoproliferative disease virus, a type-C retrovirus, is the etiologic agent of a naturally acquired lymphoproliferative disorder in turkeys. The disease is characterized by rapid induction of lymphoproliferative lesions with morphologic and histopathologic features resembling those of reticuloendotheliosis. Owing to lack of overt clinical manifestations, early detection of lymphoproliferative disease virus is essential for preventing the rapid horizontal spread of the disease that can decimate flocks. We describe development of a simple, rapid, sensitive, and highly specific assay, using the polymerase chain reaction, capable of providing differential diagnosis of the disease soon after infection.